FIG 4.

X. nematophila and P. luminescens partially suppress the melanization response of D. melanogaster. (A) Melanization from S. carpocapsae infection. The panel shows a representative D. melanogaster larva (left) and pupa (right) melanized by axenic S. carpocapsae IJs. (B) X. nematophila and P. luminescens inhibit melanization. Infection of D. melanogaster larvae with axenic S. carpocapsae (left graph) or H. bacteriophora (right graph) IJs resulted in a higher percentage of melanized fly larvae or pupae than infection with symbiont IJs. *, P < 0.05, unpaired t test. No melanization was observed in fly larvae not exposed to IJs. Melanization was scored at 48 h postexposure to IJs. Error bars represent standard errors of the means (n = 7 to 8 trials).